<div class="panel panel-primary">
  <div class="panel-heading">NgIf演示</div>
  <div class="panel-body">
    <p *ngIf="isShow" style="background-color:red">显示还是不显示？</p>
    <button class="btn btn-success" (click)="toggleShow()">控制显示还是隐藏</button>
  </div>
</div>